Jump to content

Favorite Trilobites In Your Collection!


paleozoicfish

Recommended Posts

After a long wait and a new air compressor, my prep guy(aka my father) finally finished it. It's one of my many favorites and quite rare to find one this large and well preserved.

Thaleops ovata

Ordovician (Blackriverian)

Mifflin member of the Platteville formation

Southwest Wisconsin

post-3840-0-57206400-1321749886_thumb.jpg

Nice Caleb!

Link to comment
Share on other sites

OK this is my latest favorite, though that status depends on what you guys say about it: Is it overprepped, missing its shell? The matrix around it also seems to be pitted as if by CP 9361 then blasted a bit to cover it up...

Hope I didn't overpay..

Pseudogygites latimarginatus, Bowmanville, Ont. (any more info I should add?)

post-4372-0-78478100-1322703572_thumb.jpg

post-4372-0-38139900-1322703625_thumb.jpg

Link to comment
Share on other sites

Ok have not posted in awhile and new bugs have made their way to my collection, some prizes from western US Cambrian I had not even hoped I might acquire, but I have been blessed in these new additions and I share with the rest of you who love bugs as much as I do :)

OK this is a old, lower Cambrian bug from Nevada that is very interesting, thin skinned, pretty rare from what I can tell. While most classify it as: Esmeraldina rowei, some feel there are distinct species amongst the many varieties, 3 of which are "commonly" seen in a very, very rare early Cambrian bug, all are from the Montenegro Mbr, of the Campito Formation, Esmeralda County, Nevada:

First is the wide-bodied, long genal spine version, this specimen and its contortion show how soft these thin-skinned early Cambrian bugs were:

The second is also a wide body form, but called "longhorn version" by some because of the spines at back of cephalon, some call this another species/genus name "Palmettaspis"

Finally here is the form of Esmeraldina rowei that has long narrow body and short genals. This one is not prepped back with negative and positive like the first two I have so I have a positive and negative:

Here is a small writeup I found on web at Western Trilobites (http://www.westerntrilobites.com/trilobites/Esmeraldina-Palmettaspis/Esmeraldina-Palmettaspis.htm)

about these varieties of this bug:

Name: Esmeraldina rowei (Walcott, 1910)

Locality: Esmeraldina County, Nevada

Stratigraphy: Montenegro Member of the Campito Formation, Lower Cambrian

Remarks: There are three "forms" of Esmeraldina rowei in this interval, the typical form, the narrow form and a wide form.These were originally described these as three separate species, but dividing a large collection of cephala into separate species reveiled a continuum of diagnosed morphologies, such that separate species were not warranted. J. Stewart Hollingsworth discussed the possible causes of this variability at length in a paper, eventually concluding that these forms may be resolved into separate species, but it will likely take centimeter-scale collecting through the trilobite interval to prove that there are distinct ranges within the variants of E. rowei.

According to Hollingsworth "The narrow form here has a simple pygidium as you have illustrated [the typical and wide forms have pygidia with stronger pleural ribs sometimes extending into blunt spines (See Fritz, 1995, fig. 6.12)]. The narrow glabella is certainly reminiscent of the glabella configuration of Palmettaspis consorta, hence the early confusion Bill Fritz and I had with this form, but the glabella extends to the anterior border without a distinct preglabellar field. The border is stronger, and more elevated. Also the cephalon has a sculpture of fine granules, which are often coarser on the other forms of E. rowei. An illustration of these variations within E. rowei and a distinct new species (named in my article now in press) of Esmeraldina from the same beds (E. elliptica) is attached.

Edited by dinoruss
Link to comment
Share on other sites

Wonderful trilobites Russ... let me know if you need either paper by Fritz or Hollingsworth... too large to post here! :P

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

Now to some other nice Cambrian bugs I thought the Esmeraldina rowei (Walcott, 1910) should have its own post in this thread....

Bristolia bristolensis, Lower Cambrian, Pioche Shale Fm. Klondike Gap, Pioche, Lincoln County, Nevada

Nevadia weeksi

Lower Cambrian, Poleta Fm, Esmeralda County, Nevada:

And finally a special Zacanthoides I just got, Z. Liddelli This is supposedly from Spence, but also known from Chisolm I believe, it is a new species so I do not know

much about it yet. But characterized by the long series of spines along the axial lobe all along its thorax.

Link to comment
Share on other sites

Wonderful trilobites Russ... let me know if you need either paper by Fritz or Hollingsworth... too large to post here! :P

I would love to get my hands on those articles. I cannot find access to them anywhere. I really want to bone up on this bug, very interesting and intriguing to me and I do not have much on this lower cambrian bug!

Thanks!

Russ

Edited by dinoruss
Link to comment
Share on other sites

I would love to get my hands on those articles. I cannot find access to them anywhere. I really want to bone up on this bug, very interesting and intriguing to me and I do not have much on this lower cambrian bug!

Thanks!

Russ

My pleasure of course... shoot me a PM with your email address. Just curious if you have the Robison/Babcock paper posted earlier today at yahoo.trilobite? A few interesting Zacanthoides there for you to consider...

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

My pleasure of course... shoot me a PM with your email address. Just curious if you have the Robison/Babcock paper posted earlier today at yahoo.trilobite? A few interesting Zacanthoides there for you to consider...

No have not seen that yet either, I have not been on yahoo as much lately as I have trouble with my password and login being remembered by my system so I have let it lie somewhat...

Link to comment
Share on other sites

Nice Cambrian trilobites Russ!

Love the Bristolia and the Zacanthoides!! :startle: :startle:

The paper by Robison and Babcock is exceptional!!!!!

Dan

Edited by palaeopix
Link to comment
Share on other sites

Nice Cambrian trilobites Russ!

Love the Bristolia and the Zacanthoides!! :startle: :startle:

Dan

Second that and nice to bump into Dan... :D

Russ, sending all three your way... Enjoy! :)

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

... nice to bump into Dan... :D

Hey Scott,

great to bump into this thread again!

If you wouldn't mind I'd love copies of the papers by Fritz and Hollingsworth too!

Dan

Link to comment
Share on other sites

Second that and nice to bump into Dan... :D

Russ, sending all three your way... Enjoy! :)

Thanks looking out for them Scott!

Link to comment
Share on other sites

Nice Cambrian trilobites Russ!

Love the Bristolia and the Zacanthoides!! :startle: :startle:

The paper by Robison and Babcock is exceptional!!!!!

Dan

Thanks Dan, I am enjoying them as new additions. It is amazing the variety of lower Cambrian bugs from out there, I had no idea....til my friend Ed got me going into this and now I have some pretty awesome bugs to enjoy, and am glad to share with you as well these pics... Looking forward to the papers, there seems to be alot to the Zaks that I am just learning about!

Russ

Link to comment
Share on other sites

Ok found the photos of one more Zacanthoides, also supposedly a new species according to Ed from whom I traded for it:

Link to comment
Share on other sites

Nice Cambrian trilobites Russ!

Love the Bristolia and the Zacanthoides!! :startle: :startle:

The paper by Robison and Babcock is exceptional!!!!!

Dan

You are right, been looking at the papers now, that paper is one I had been waiting to see somewhere, it has the new species of zak I apparently have named in it as well. Lots of cool reading ahead for me!

Link to comment
Share on other sites

My pleasure of course... shoot me a PM with your email address. Just curious if you have the Robison/Babcock paper posted earlier today at yahoo.trilobite? A few interesting Zacanthoides there for you to consider...

Thanks for sending and bringing this third one up. It does have some cool zak info I was wanting to learn about. this is a very recent pub it will be hightly useful to me as I try to learn more about these cambrian bugs.

russ

Link to comment
Share on other sites

Wonderful trilobites Russ... let me know if you need either paper by Fritz or Hollingsworth... too large to post here! :P

Both those are great Scott! Lots of reading on the esmers! They are so variable, even though they have a general set of types. Interesting reading, well time for bed, more reading on these for tomorrow. Some good winter time learning and reading! Thanks again!

Russ

Link to comment
Share on other sites

Did anyone catch my earlier post above? I had some questions.. (I know it wasn't nearly as interesting as Dinoruss' new additions)

Link to comment
Share on other sites

OK this is my latest favorite, though that status depends on what you guys say about it: Is it overprepped, missing its shell? The matrix around it also seems to be pitted as if by CP 9361 then blasted a bit to cover it up...

Hope I didn't overpay..

Pseudogygites latimarginatus, Bowmanville, Ont. (any more info I should add?)

Did anyone catch my earlier post above? I had some questions.. (I know it wasn't nearly as interesting as Dinoruss' new additions)

Oops... sorry Eric as there was a lot going on with the sudden flurry of trilobites posted by Russ. Although you have the basic information, the only thing I would have suggested is picking up a copy of the ROM's classic monograph:

The Ordovician Trilobite Pseudogygites Kobayashi in Eastern and Arctic North America

Royal Ontario Museum Publications in Life Sciences (November 2, 1979) Rolf Ludvigsen

Happily this long out of print publication was finally digitized by the ROM at the internet archive in September 2011.

:DPDF LINK B)

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

Thanks so much for posting these wonderful wonderful trilobites! Glad to see this amazing post comes back again!

Link to comment
Share on other sites

I seldom read those very serious academic papers other than my own field, but I can tell from the pictures that it is an exceptional paper!

Nice Cambrian trilobites Russ!

Love the Bristolia and the Zacanthoides!! :startle: :startle:

The paper by Robison and Babcock is exceptional!!!!!

Dan

Link to comment
Share on other sites

Oops... sorry Eric as there was a lot going on with the sudden flurry of trilobites posted by Russ. Although you have the basic information, the only thing I would have suggested is picking up a copy of the ROM's classic monograph:

The Ordovician Trilobite Pseudogygites Kobayashi in Eastern and Arctic North America

Royal Ontario Museum Publications in Life Sciences (November 2, 1979) Rolf Ludvigsen

Happily this long out of print publication was finally digitized by the ROM at the internet archive in September 2011.

:DPDF LINK B)

Thanks Scott as always.. without reading in depth yet, by the pics/captions it does appear my specimen is just the internal mould, dang it. oh well, cant win 'em all.

Link to comment
Share on other sites

Are you sure Eric? It doesn't look like an internal mold to me, but you have the actual specimen and I just have your photos to go by. Your specimen seems pretty decent to me.

That whole Pseudogygites latimarginatus name still bugs me. P. canadensis was based on an exquisite complete specimen, and P. latimarginatus was based on a poor pygydium that wasn't even recognized as a Pseudogygites for many years. Sometimes the law of priority sucks.

Don

Link to comment
Share on other sites

The Pseudos typically have a very thin layer of light colored integument. You can see a few flakes here and there on Eric's example.

Attached are a few specimens with most of the integument (shell) still intact.

post-4301-0-35872600-1322883257_thumb.jpg

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...